How to share a model with new user

How to share an existing model with a new user

If a new user can't see an existing model, it's usually because the model was created before they were granted permission to access the modelling environment (its a security feature). Take the following steps to share it: 

Copying an existing model to the latest output

To make an existing model available to the new user, the author (or a user with appropriate access) needs to copy the model across to the latest output using a data refresh.
Steps are documented here: Performing a Data Refresh 

Sharing the model

Copying the model to the latest output doesn't automatically make it visible to anyone. By default, every model is private, so it still needs to be explicitly shared with each intended user.
Steps to share a model: Sharing a Model 

Note: A user can only be shared a model if they already have modelling access. 

Why this happens

Modelling access is stored in the backend configuration. When a new user needs access, a new output is published to apply the change and that new output is what actually grants it. From that point on, the user can see new outputs going forward, but not outputs published before they were added.
So if a model still sits in an old output, a newly added user won't see it, even once they have modelling access, until it's copied across.
Tip: every output has a date at the end of its URL, showing when it was published. Use this to quickly check whether a model is sitting in an output from before or after a user was added.